15.6.4.5 memcached Detail Statistics

For memcached 1.3.x and higher, you can
enable and obtain detailed statistics about the get, set, and
del operations on theindividual keys stored in the cache, and
determine whether the attempts hit (found) a particular key.
These operations are only recorded while the detailed stats
analysis is turned on.

To enable detailed statistics, you must send the stats
detail on command to the memcached
server:

Individual statistics are recorded for every
get, set and
del operation on a key, including keys that
are not currently stored in the server. For example, if an
attempt is made to obtain the value of key
abckey and it does not exist, the
get operating on the specified key are
recorded while detailed statistics are in effect, even if the
key is not currently stored. The hits, that
is, the number of get or
del operations for a key that exists in the
server are also counted.

To turn detailed statistics off, send the stats detail
off command to the memcached
server:

You can use the detailed statistics information to determine
whether your memcached clients are using a
large number of keys that do not exist in the server by
comparing the hit and get
or del counts. Because the information is
recorded by key, you can also determine whether the failures or
operations are clustered around specific keys.